flocks

This is the time of year when the best way to find warblers is to look for feeding flocks or tribes of Black-capped Chickadees. For some reason, visiting warblers (yes, they are well into migration mode) tend to latch on to the chickadees. Perhaps the chickadees, which are locals, know where to find food and the warblers somehow know this. Or perhaps, the chickadees simply stir up insects from the bark and leaves of the trees and make it easier for the warblers to participate in the feast. Oddly enough, this trick doesn't seem to work as well with the Tufted Titmice who also move in small family groups, occasionally attaching themselves to the chickadee flocks as well. Usually there's a Downy Woodpecker or two and often wrens -- Carolina or House -- join in as well, at least temporarily. This habit of feeding in flocks is quite normal in the tropics; here we see it starting in late summer and through the fall and winter. Some birds flock to their kind; typically we see the formation of Common Grackle flocks, Red-wing Blackbird flocks, etc. But other birds ignore conventional wisdom about 'birds of a feather' and move in mixed flocks.

This morning's warblers were all in a small chickadee flock at the head of the marsh: Common Yellowthroat, Black-and-white Warblers, Northern Waterthrush and American Redstart.

Eric Salzman